John Versace, 23, was shot dead in the driveway of his Condell Park home in Sydney's southwest on May 19, with no signs he had links to criminal activity.
Police on Tuesday charged Blaze Collins, 21, with his murder, alleging he was the gunman.
It comes almost a week after two alleged getaway drivers, aged 43 and 19, were also charged with murder.
Collins did not apply for bail when he faced the Burwood Local Court on Tuesday, with the matter to return on January 21.
Police had already charged Collins with a string of offences including participating in a criminal group, with authorities linking him to an emerging crime network known as G7.
Police have previously alleged G7 members are regularly contracted in to other criminal groups to carry out offences on their behalf.
Collins was charged with murder in Silverwater prison, where he has been on remand since August.
He was already facing charges including recklessly causing grievous bodily harm and aggravated breaking and entering, along with gun and drug possession charges.
Mr Versace was backing his car into his driveway about 10.30pm on May 19 before another vehicle pulled up and parked him in.
A man holding what is believed to be a Glock pistol got out of the vehicle and fired up to 10 bullets at the plumber.
"(Collins) has appraised Mr Versace in the driveway ... and fired multiple shots from a pistol, which proved fatal," Detective Superintendent Jason Box told reporters on Tuesday.
"There is nothing to suggest that Mr Versace was anything but a hard-working young man who was living at home with his family, he was much loved and trying to set himself up for the rest of his life."
The 43-year-old man was accused of planning the murder and driving the shooter to the house, while the younger driver allegedly met the duo soon after and drove them to another location.
The 19-year-old also allegedly helped plan and prepare for the murder by acquiring and staging the cars.
After the killing, Mr Versace's sister took to social media to reveal the heartbreak her family was feeling.
"John, no words can describe the pain we are all feeling and will continue to feel for the rest of our lives," she wrote on Facebook.
"We are so lucky and blessed to have had the time we had with you but your life was cut too short ... you did not deserve this."
After the driver duo were charged last week, Det Supt Box did not allege a motive for the killing.Â
Mr Versace's murder occurred during a spike in public shootings across the city.
Less than a week after his death, two men were hospitalised after a gunman sprayed a ute with bullets in Granville, and in October, former UFC fighter Suman Mokhtarian was gunned down while out for a walk.
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